The following includes information that may be useful in understanding the present invention(s). It is not an admission that any of the information provided herein is prior art, or material, to the presently described or claimed inventions, or that any publication or document that is specifically or implicitly referenced is prior art.
1. Field of the Invention
The present invention relates generally to the field of arc welding tools, and more particularly, to a welding rod expander assembly adapted to expand a welding rod to a remote location.
2. Description of the Related Art
Arc welding, more specifically, shielded metal arc welding (SMAW), employs an electric arc to melt a work material and a welding rod to lay a weld. An electric current forms the electric arc between the electrode (welding rod) and the work material to be welded.
The welding procedure is dependent on the electrode rod, composition of the work material, and location of a joint to be welded. Minimal skill is required for welding a flat joint. Further, welding the flat joint may be done with a welding rod that may melt quickly but solidify slowly. However, welding sloped, vertical or upside-down joint, termed “out of position,” takes steady hands and an eye for detail. Further, welding joints at a remote location i.e., an inaccessible location is a cumbersome process and also associated with risk to life and limb. In order to weld a joint at the remote location, a welder may have to periodically stop the welding procedure in order to stretch to the remote location. Further, the welder may have to first weld more than one welding rod together to increase the length of the welding rod in order to make the welding rod reach the remote location. Such an extended welding rod may be subjected to breakage which may present a greater danger to the welder.
A welder will often need to make a weld in a location that he is not able to fit into, or easily see the area needing to be welded. Sometimes there is not even enough space for the welder's face shield to fit into. A common practice that welders employ in these situations is to bend the welding rod at 45 degrees or greater to be able to perform the weld at the correct angle. The end of the rod must be the correct distance from the joint to be welded and must also be at a correct angle to the work piece. This is even more critical in out of position welding. An incorrect weld angle on an out of position work piece will tend to undercut the parent metal and trap slag, resulting in a bad weld. When a welder bends the welding rod to make a weld, flux is broken off of the welding rod leaving bare metal around the bent area, and creating greatly increased chances of arcing to an unintended object.
A second problem with this practice is that each rod that is bent looses approximately 60 percent of the length of the weld it could have made. The waste increases cost and creates a greater chance for inclusions of slag into the weld because the welder has to stop and start several more times than he would have if he had been able to bum the whole length of rod. It is when a welder starts and when he stops a welding arc that he has a very high probability of trapping slag deep into the weld weakening the welded joint. When a welder has to bend rods to achieve the correct angle, he also multiplies the chances of a bad weld because of the increased amount of starts and stops. The electrode holder is designed to clamp the electrode at various angles to the holder, but very often the angle needs to be made at a distance from the clamp. Existing clamps are not designed for this. A cost effective and innovative solution to the problem is needed.
Various attempts have been made to solve the above-mentioned problems such as those found in U.S. Pat. Nos. 6,444,951; and 4,588,252; 3,219,793; 4,194,107; 2,324,924; and 2,498,241. This prior art is representative of electrode holders. None of the above inventions and patents, taken either singly or in combination, is seen to describe the invention as claimed.
Ideally, an electrode holder would allow the electrode to be adjustably lengthened and angled at various distances from the hand of the user, and yet, would operate reliably and be manufactured at a modest expense. Thus, a need exists for a reliable welding rod expander assembly to allow the welder work using proper welding practices and to avoid the above-mentioned problems.